Feeding apparatus having a feed-in-roller arranged to move in a linear direction to prevent curling of the leading edge of a paper during the feeding operation

ABSTRACT

A paper-feeding mechanism includes a paper tray to receive a stack of papers therein, and a paper-separating plate disposed below and extending frontwardly from the paper tray. A feed-in roller is disposed in front of the paper tray in such a manner that rotation of the feed-in roller results in feeding operation of a sheet of paper from the paper tray via the paper-separating plate. An urging member urges constantly the feed-in roller to push the papers toward the paper tray.

FIELD OF THE INVENTION

The present invention relates to a paper feeding apparatus, more particularly to a design to arrange a feed-in roller of the feeding apparatus to move in a linear direction so as to prevent curling of the leading edge of a paper sheet during the feeding operation.

DESCRIPTION OF THE RELATED ART

FIG. 1 is a perspective view of a paper-feeding mechanism 10 of a conventional feeding apparatus (such as a facsimile machine, a printer and a digital copier), and includes a paper tray 12, a paper-separating member 14 disposed below the paper tray 12, an axle 16 transversely disposed above the paper tray 12, a roller carrier 18 mounted on the axle 16, and a feed-in roller 19 jounrnalled to a free end of the roller carrier 18.

During the feeding operation, the feed-in roller 19 abuts against the stack of paper 20 so as to generate a friction therebetween, as shown in FIG. 2A. The paper sheets 20 are successively fed into the conventional feeding apparatus upon rotation of the feed-in roller 19 that is driven by a swing gear set (see FIG. 2A). The leading edge of each paper sheet 20 curls upward due to abutment of the paper-separating plate 14 (not visible), and is led toward the feeding mouth (not visible) of the conventional feeding apparatus. Note that during the feeding operation and by virtue of the reduction of paper 20 in the paper tray 12, the contact points P1, P2 between the feed-in roller 19 and the paper 20 change ceaselessly. In other word, the feed-roller 19 travels along a curved path S. Under this condition, two different distances D1, D2 are measured respectively between the contact points P1, P2 of the feed-in roller 19 and the paper-separating plate 14 when the paper tray 12 is loaded with the stack of papers 20 or not (see FIGS. 2A and 2B).

FIG. 3 shows the traveling path S′ of a feed-in roller 29 used in the paper-feeding mechanism of another conventional feeding apparatus, wherein the axle 26 for holding the roller carrier 28 is disposed at an elevation below the paper tray 22 and the paper-separating plate 24. Since the roller carrier 28 rotates about the axle 26, the contact point between the feed-in roller 29 and the paper 20 changes ceaselessly.

It is noticed that the abutment force between the leading edge of the paper sheet and the paper-separating member 14 is increased when the distance between the feed-in roller and the paper-separating member grows larger. In other word, the thicker the paper sheet, the more occurrence of untimely curling and damage of the leading edge of the paper sheet can result while being fed into the mouth of the conventional feeding apparatus.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a paper-feeding mechanism for a feeding apparatus, the paper-feeding mechanism including a paper feed-in roller arranged in such a manner to move in a linear direction so as to maintain a constant distance between the feed-in roller and a paper-separating plate so as to avoid the aforesaid drawback encountered during use of the conventional feeding apparatus.

A paper-feeding apparatus of the present invention includes a housing, a feed-in roller and an urging member. The housing includes: a paper tray for receiving a plurality of papers therein, and a paper-separating plate disposed below the paper tray, and extending therefrom in a longitudinal direction. The housing further defines a guide slot unit formed neighboring to the paper tray. The guide slot and the paper tray cooperatively define a predetermined angle therebetween. The feed-in roller is disposed above the paper tray and is movably associated with the guide slot in such a manner that rotation of the feed-in roller results in feeding operation of a sheet of paper from the paper tray via the paper-separating plate. An urging member is disposed between the housing and the feed-in roller for constantly urging the feed-in roller move toward the paper tray along the guide slot.

In another aspect of the present invention, a paper-feeding mechanism for a feeding apparatus is proposed. The feeding apparatus includes a housing and a mouth for access into the housing. The paper-feeding mechanism includes: a paper tray for receiving a plurality of papers therein; a paper-separating plate disposed below and frontwardly of the paper tray, and extending therefrom in a longitudinal direction toward the mouth; a guide slot disposed at an elevation above the paper-separating plate, disposed neighboring to the paper tray, the guide slot cooperating with the paper tray to define an angle therebetween; a feed-in roller disposed rotatably in front of the paper tray and associated slidably with the guide slot in such a manner that rotation of the feed-in roller results in feeding operation of the paper sheet from the paper tray into the housing via the paper-separating plate and the mouth; and a roller carrier disposed above the paper-separating plate to permit journalling of the feed-in roller to the roller carrier.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a perspective view of a paper-feeding mechanism of a conventional feeding apparatus;

FIG. 2A is a side view, illustrating when a paper tray of the conventional feeding apparatus is loaded with a stack of papers;

FIG. 2B is a side view, illustrating when a paper tray of the conventional feeding apparatus is unloaded;

FIG. 3 is a side view, illustrating when a paper tray of another conventional feeding apparatus is unloaded;

FIG. 4A is a side view, illustrating when a paper tray in the first preferred embodiment of a paper-feeding mechanism according to the present invention is unloaded;

FIG. 4B is a side view, illustrating when the paper tray in the first preferred embodiment of the paper-feeding mechanism according to the present invention is loaded with a stack of papers;

FIG. 5A is a side view, illustrating when a paper tray in the second preferred embodiment of the paper-feeding mechanism according to the present invention is unloaded;

FIG. 5B is a side view, illustrating when the paper tray in the second preferred embodiment of the paper-feeding mechanism according to the present invention is loaded with a stack of papers;

FIG. 6 is a side view, illustrating when a paper tray in the third preferred embodiment of the paper-feeding mechanism according to the present invention is unloaded;

FIG. 7A is a side view, illustrating when a paper tray in the fourth preferred embodiment of the paper-feeding mechanism according to the present invention is unloaded;

FIG. 7B is a side view, illustrating when the paper tray in the fourth preferred embodiment of the paper-feeding mechanism according to the present invention is loaded with a stack of papers;

FIG. 8A is a side view, illustrating when a paper tray in the fifth preferred embodiment of the paper-feeding mechanism according to the present invention is unloaded; and

FIG. 8B is a side view, illustrating when the paper tray in the fifth preferred embodiment of the paper-feeding mechanism according to the present invention is loaded with a stack of papers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Before the present invention is described in greater detail with reference to the following preferred embodiments, it should be noted that same reference numerals have been used to denote similar elements through out the specification.

Referring to FIG. 4A, the first preferred embodiment of a paper-feeding mechanism according to the present invention is used a feeding apparatus, such as a digital copier or a fax machine or a printing machine, and includes a housing (not show), a feed-in roller 109, and an urging member.

As illustrated, the housing (not visible) defines an inclined paper tray 102 receiving a stack of papers 120 therein (see FIG. 4B), and a paper-separating plate 104 disposed below and frontwardly of the paper tray 102. The separating plate 104 extends from the paper tray 102 in a longitudinal direction toward a feeding mouth (A) of the fax machine (not shown). The housing (not visible) further defines a guide slot 106 that is disposed neighboring to the paper tray 102, that is defined by a groove-forming wall 106W and that cooperates with the paper tray 102 to define an angle (X) therebetween. The guide slot 106 generally extends in a direction parallel to the paper-separating plate 104.

The feed-in roller 109 is disposed frontwardly of the paper tray 102 to abut against the paper sheets 120 in such a manner to generate a friction force therebetween such that rotation of the feed-in roller 109 in the clockwise direction results in feeding operation of each paper sheet 120 successively from the paper tray 102 via the paper-separating plate 104. The urging member urges constantly the feed-in roller 109 to abut against the paper tray 102. A roller carrier 108 is provided to carry the feed-in roller 109 rotatably thereon, and has spaced-apart first and second engaging tongues 122, 124 slidably engaging the groove-forming wall 106W of the guide slot 106 such that moving distance or moving range of the roller carrier 108 is restricted by the thickness of the paper sheets 120. The urging member can be a tension spring 110 having a mounting end fastened securely to the housing and an urging end coupled to the roller carrier 108 in such a manner to bias the feed-in roller 109 abutting against the paper tray 102.

The first preferred embodiment further includes a driving motor (not shown) and a swing gearset 130 consisting of a swing arm 132, a driving gear 134 mounted rotatably on the swing arm 132, and a transmission gear 136 disposed between and synchronously meshed with the driving gear 134 and the feed-in roller 109. The driving gear 132 is co-axially connected to the driving motor (not shown) such that the feed-in roller 109 is driven in the clockwise direction upon activation of the driving motor.

Note the distance between the feed-in roller 109 and the paper-separating plate 104 is constant regardless of the thickness of the paper sheets by virtue of movement of the roller carrier 108 along a linear direction in the guide slot 106. In the same manner, the abutment force between the leading edge of each paper sheet 120 and the paper-separating plate 104 remain the same throughout the feeding operation, thereby eliminating the curling occurrence of the leading edge of the paper sheet encountered during use of the conventional feeding apparatus.

Referring to FIGS. 5A and 5B, the second preferred embodiment of the paper-feeding mechanism of the present invention is shown to have the structure similar to the previous embodiment. The only difference resides in the roller carrier 108 has an elongated engaging tongue 126 slidably engaging the groove-forming wall defining the guide slot 106. The engaging tongue 126 has a width similar to that of the guide slot 106 so as to result in stable movement of the engaging tongue 126 within the guide slot 106.

Referring to FIG. 6, the third preferred embodiment of the paper-feeding mechanism of the present invention is shown to have the structure similar to the first preferred embodiment. The main difference resides in that the groove-forming wall of the guide slot includes a front wall portion defining a front slot section 144 and a rear wall portion defining a rear slot section 142. The roller carrier 108 has spaced-apart front and rear engaging tongues 154, 152 respectively and slidably engaging the front and rear wall portions of the front and rear slot sections 144, 142.

Referring to FIGS. 7A and 7B, the fourth preferred embodiment of the paper-feeding mechanism of the present invention is shown to have the structure similar to the first preferred embodiment. The only difference resides in the urging member employed herein is a torsion spring sleeved around a mounting post in the housing (not shown) and having a mounting end fastened securely to the housing and an urging end coupled to the roller carrier 109 in such a manner to bias the feed-in roller 109 abutting against the paper tray 102.

Referring to FIGS. 8A and 8B, the fifth preferred embodiment of the paper-feeding mechanism of the present invention is shown to have the structure similar to the first preferred embodiment. The only difference resides in no urging member is employed herein and the guide slot 106 is arranged in such a manner to incline with respect to a horizontal line H about an acute angle Y in order to permit normal resting of the feed-in roller 109 on the paper tray 102 by virtue of its own weight and gravity.

As is understood by a person skilled in the art, the foregoing preferred embodiment of the present invention is an illustration of the present invention rather than limiting thereon. It is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure. 

1. A paper-feeding apparatus comprising: a housing including a paper tray for receiving a plurality of papers therein, a paper-separating plate disposed below said paper tray, and extending therefrom in a longitudinal direction, said housing further defining a guide slot formed neighboring to said paper tray, said guide slot and said paper tray cooperatively defining a predetermined angle therebetween; a feed-in roller disposed above said paper tray and movably associated with said guide slot in such a manner that rotation of said feed-in roller results in feeding operation of a sheet of paper from said paper tray via said paper-separating plate; and an urging member disposed between said housing and said feed-in roller for constantly urging said feed-in roller move toward said paper tray along said guide slot.
 2. The paper-feeding apparatus according to claim 1, wherein said guide slot extends in a direction parallel to said longitudinal direction.
 3. The paper-feeding apparatus according to claim 1, further comprising a driving motor and a swing gearset operably connected to said driving motor for rotating said feed-in roller.
 4. The paper-feeding apparatus according to claim 1, wherein said urging member includes a tension spring having a mounting end fastened securely to said housing and an urging end coupled to said feed-in roller in such a manner to bias said feed-in roller abutting against said paper tray.
 5. The paper-feeding apparatus according to claim 1, further comprising a roller carrier that has two spaced-apart front and rear engaging tongues slidiably engaging said guide slot.
 6. The paper-feeding apparatus according to claim 5, wherein said guide slot includes a front slot section and a rear slot section, said spaced-apart engaging tongues of said roller carrier slidably engaging said front and rear slot sections of said guide slot, said feed-in roller being journalled to said roller carrier between said front and rear engaging tongues.
 7. The paper-feeding apparatus according to claim 1, further comprising a roller carrier having an elongated engaging tongue slidably engaging said guide slot, said feed-in roller being journalled to said roller carrier frontwardly of said elongated engaging tongue.
 8. A paper-feeding mechanism for a feeding apparatus that includes a housing and a mouth for access into the housing, the paper-feeding mechanism comprising: a paper tray for receiving a plurality of papers therein; a paper-separating plate disposed below said paper tray; a feed-in roller disposed above said paper tray and abutting against said papers in such a manner that rotation of said feed-in roller results in feeding operation of the paper sheet from said paper tray into the housing via said paper-separating plate and the mouth; a roller carrier disposed above said paper-separating plate to permit adjusting the distance between said feed-in roller and said paper tray according to the thickness of the papers; and an urging member connected to said roller carrier for urging said feed-in roller move toward said paper tray.
 9. The paper-feeding mechanism according to claim 8, wherein said urging member includes a tension spring having a mounting end adapted to be fastened securely to the housing and an urging end coupled to said roller carrier in such a manner to bias said feed-in roller move toward said paper tray.
 10. The paper-feeding mechanism according to claim 8, wherein said urging member includes a torsion spring having a mounting end adapted to be fastened securely to the housing and an urging end coupled to said roller carrier in such a manner to bias said feed-in roller move toward said paper tray.
 11. The paper-feeding mechanism according to claim 8, wherein said paper tray defines a first thickness when loaded with the plurality of papers and a second thickness when non-loaded, said first and second thickness cooperatively defining a moving range for said roller carrier.
 12. The paper-feeding mechanism according to claim 8, further comprising a driving motor and a swing gearset operably connected to said driving motor for rotating said feed-in roller.
 13. A paper-feeding mechanism for a feeding apparatus that includes a housing and a mouth for access into the housing, the paper-feeding mechanism comprising: a paper tray for receiving a plurality of papers therein; a paper-separating plate disposed below said paper tray, and extending therefrom in a longitudinal direction toward the mouth; a guide slot disposed at an elevation above said paper-separating plate, disposed neighboring to said paper tray, said guide slot and said paper tray defining a predetermined angle therebetween; a feed-in roller disposed above said paper tray and associated movably with said guide slot in such a manner that rotation of said feed-in roller results in feeding operation of the paper sheet from said paper tray into the housing via said paper-separating plate and the mouth; and a roller carrier disposed above said paper-separating plate to permit journaling of said feed-in roller.
 14. The paper-feeding mechanism according to claim 13, wherein said paper tray defines a first thickness when loaded with the plurality of papers and a second thickness when non-loaded, said first and second thickness cooperatively defining a moving range for said roller carrier.
 15. The paper-feeding mechanism according to claim 13, further comprising a driving motor and a swing gearset operably connected to said driving motor for rotating said feed-in roller.
 16. A paper-feeding mechanism for a feeding apparatus that includes a housing and a mouth for access into the housing, the paper-feeding mechanism comprising: a paper tray for receiving a plurality of papers therein; a paper-separating plate disposed below said paper tray, and extending therefrom in a longitudinal direction toward the mouth; a feed-in roller disposed above said paper tray and abutting against said papers in such a manner that rotation of said feed-in roller results in feeding operation of the paper sheet from said paper tray into the housing via said paper-separating plate and the mouth; a roller carrier disposed at an elevation above said paper-separating plate to permit journaling of said feed-in roller to said roller carrier; and an urging member connected to said roller carrier for constantly urging said roller carrier so as to bias said feed-in roller move toward said paper tray.
 17. The paper-feeding mechanism according to claim 16, wherein said urging member includes a tension spring having a mounting end adapted fastened securely to the housing and an urging end coupled to said roller carrier in such a manner to bias said feed-in roller abutting against said paper tray.
 18. The paper-feeding mechanism according to claim 16, wherein said urging member includes a torsion spring having a mounting end adapted to be fastened securely to the housing and an urging end coupled to said roller carrier in such a manner to bias said feed-in roller move toward said paper tray.
 19. The paper-feeding mechanism according to claim 16, wherein said paper tray defines a first thickness when loaded with the plurality of papers and a second thickness when non-loaded, said first and second thickness cooperatively defining a moving range for said roller carrier.
 20. The paper-feeding mechanism according to claim 16, further comprising a driving motor and a swing gearset operably connected to said driving motor for rotating said feed-in roller. 